I. In the feudal system an ecclesiastical fief followed all the laws laid down for temporal fiefs. The suzerain, e.g. bishop, abbot, or other possessor, granted an estate in perpetuity to a person, who thereby became his vassal. As such, the grantee at his enfeoffment did homage to his overlord, took an oath of fealty, and made offering of the prescribed money or other object, by reason of which he held his fief. These requirements had to be repeated as often as there was a change in the person of the suzerain or vassal. These fiefs were granted by churchmen to princes, barons, knights, and others, who thereupon assumed the obligation of protecting the church and domains of the overlord. This system of feudal tenure was not always restricted to lands, as church revenues and tithes were often farmed out to secular persons as a species of ecclesiastical fief. Strictly speaking, however, a fief was usually defined as immovable property whose usufruct perpetually conceded to another under the obligation of fealty and personal homage. A fief was not ecclesiastical simply because its overlord was a churchman; it was requisite also that the domain granted should be church property. Lands, which belonged to the patrimony of an ecclesiastic, became a secular fief if he bestowed them on a vassal.

All fiefs were personal and hereditary, and many of the latter could be inherited by female descent. Fiefs bestowed by the Church on vassals were called active fiefs; when churchmen themselves undertook obligations to a suzerain, the fiefs were called passive. In the latter case, temporal princes gave certain lands to the Church by enfeoffing a bishop or abbot, and the latter had then to do homage as pro-vassal and undertake all the implied obligations. When these included military service, the ecclesiastic was empowered to fulfil this duty by a substitute. It was as passive fiefs that many bishoprics, abbacies, and prelacies, as to their temporalities, were held of kings in the medieval period, and the power thereby acquired by secular princes over elections to ecclesiastical dignities led to the bitter strife over investitures. These passive fiefs were conferred by the suzerain investing the newly-elected churchman with crozier and ring at the time of his making homage, but the employment of these symbols of spiritual power gradually paved the way to exorbitant claims on the part of the secular overlords (see INVESTITURES, CONFLICT OF). Among papal fiefs were included not merely landed estates, however vast, but also duchies, principalities, and even kingdoms. When the pope enfeoffed a prince, the latter did homage to him as to his liege lord, and acknowledged his vassalage by an annual tribute. Pius V (29 Mar., 1567) decreed that, in future, fiefs belonging strictly to the Patrimony of St. Peter should be incorporated with the Pontifical States whenever the vassalage lapsed, and that no new enfeoffment take place. John, King of England, declared that he held his realm as a fief from the pope in 1213, and James II, King of Aragon, accepted the same relation for Sardinia and Corsica in 1295. The most famous papal fief was the Kingdom of Naples and Sicily, springing from investitures of 1059 and 1269. Modern conditions in Italy have made impossible any continuance of such feudal relations.

II. As to the tenure by which church lands are now held by legal titles before the civil law, see PROPERTY, ECCLESIASTICAL; and TRUSTEE SYSTEM.

III. For the perpetual tenure by incumbents of benefices and ecclesiastical dignities, see BENEFICE.